In a small saucepan add the reserved Mandarin orange juice and 1 cup of sugar, and cook over medium-high heat until thick and syrupy, about 8 minutes. Let cool to room temperature.
Reserve 4 orange segments for garnishing the Orange Fizz Cocktail. In a blender combine the cooled syrup with remaining oranges and puree. Reserve 1 cup of the blended orange mixture for Orange Fizz Cocktail. Add the heavy cream to the blender with remaining orange mixture and vodka, if desired, and blend until smooth. Pour into ice pop molds, cover, insert ice pop sticks and freeze until frozen, about 4 hours.